Continuous engine-indicator.



M. W. HOGLE.

CONTINUOUS ENGINE v INDICATOR. APPLICATION FILED PER-8,1906.

898,474. I Paten l; a Sept. 15,1908.

WITNESSES! I E W 9% F M @221, o. 0%

ATTORNEY M. w. HOGLE. CONTINUOUS ENGINE INDIOATOR.

APPLICATION FILED PER. B, 1906.

' Patented Sept. 15, 1908.

3 SHEETS-SHEET 2.

INVENTOR m 14 M 11;

WITNESSES BY 45.6% ATTORNEY M. W. HOGLE. CONTINUOUS ENGINE INDIGATOBI. APPLIOATION FILED I'E B. 8, 1906.

' tions in the steam pressure in an engine cyl- 15 an 'inproved *contmuous' engine, indicator.

' 30 engine cylinder 3", are su'ita ly Supported in a base-plate 4 and are arranged so that re- 1 QFEIQE,

' MILTON W. stem; or PITTSBURG, PENNSYLVANIA.

continuous .ENGINEJNDICATQR.

' -1\ie.898,474 Specification of Letters Patent. Patented Sept. 15, 1908.

' Appliean'on filed February a, 1906. Serial mfaeaiva.

their upper faces, with sets'of pawls 20 and 21 that are adaptedtoeng'age thec'orrespond ,ing adjacent ratcliets wand 17. The pitch of the pawls is preferablyia multiple of the 50 pitch of the teeth ongthe ratchets plus or minus a fraction thereof i1? ordelj that there may be but a smaller negligibIe'amOuntof lost motion durin operation;- In practice this arrangement as successfully obviated difliculties that might arise from lost motion.- The roll la is preferably driven from the-roll 13 bymeansofgearin 22, though,'if desired, it may be run-id e; and -therolls may be. provided/with rubber or other resilientg v coverings inorder to prevent slipping of'the- I 'recordstri f Mounterl inparallel guides'23 and 24 upon the lower face of the base-plate 4,- isaframe 25 that isadapted. to be connected with'the 75 piston or connecting fodof anengine or to any other'reciprocating part "the motionof a which is proportional to that of the piston, bymeans of a cord 26 that may be attached 9 To all whom it may concern:

Be it known that I, MILTON W. HOGLE) aciti zen'of-th'e United States, and aresident of'Pittsburg, in the county of Allegheny and '5 State ofPennsylvanial, .have invented a new and useful llnprovement in Continuous En g im-Indicators,- of which the following is a specification. My invention vrelates to indicators forsteam i engines and particularly to those which make continuous records of the variainder.

The object of my invention is to provide which shall record simultaneously the variations in stea'rnpressurein both ends'of an engine-cylinder. I l' Figure ;1 of the accompanying drawings is a View, in elevation,' of a device that embodies my invention. Fighsis plan view; et -the deviceshown in I 1g. 11. Fig, 3 is a "-view in vertical cross-section -o the device on line Ill- 111 of Fig. 1, and Fig. 4 is a diagram or record such as is traced bythe de- I -I Two pressure indicators l-and' 2 of the V ordinarytype, that areadapted to be 'connected respectively with op )Osite ends of an provided upon vopposite inner faces and in different planes w th racks27 and 28v that are adapted to engage the pinions-1'8 and 19, respectively} The frame 25 "'is.-' normally maintained in the. .p osi1, ion shown by means g5. of cords 29 and 3.0 'that are adapted to be: wound upon loosely moufi rolls 31 and 3-2 cording pencils 5 and 6 that are carried at the and that are main tained tau by means of to either end of the frame. *The frame 25 is go'. I

ends of "opppositely directed ..lever arms 7 i and 8 may move inclo'sely adjacent parallel lines without ,interference.

- in order that ,the coordinates of the curves traced by the two pencils may be substantially identical that the ends of the lever It is essential arms of the indicators bebent-so that the The pencils 5 and 6 engage-a record strip 7 sure upon the record strip 7 The position 95s.

of the pencil 40 is determined bdfore steam pressure is admitted to the cylinder by plac mg it in alinementjwith the pencils 5 and 6,

upon fanidle platen roll 9 that is rotatably [,mminted between the base-plated and a top- 45." plate 10, the recordingstrip being drawn over the platen from aroll 11 that is carried by a spindle 12, by means oi'ieed rolls .13 and 14. 'llu: feed roll I3 is mounted upon a spindle l5 thatfprojects through'the 'baseplate l and to the lower ends of which two ratcliets' l'fi and 1-7, respectively, are rigidly secured, the pitch of the teeth on the ratchets V being very small. Loosely mounted upon the lower end of the spindle 15, adjacent to which, under tlpreoi ditions indicated, should a be disposedhorizontally opposite each other 10c at the lower endot' the platen rollQ. v The outer endof a spring 42 exerts pics I sure upon-a disk 43 that is rigidly secured to the spindle 12f'and serves to maintainthe recordstrip taut, the record -roll being 1o5 mounted upon-tho spindle 12 in such a man-v nor as to prevent relative rotatioiibetween thoseparts. i i H Any suitable meansimay be employed for w holding the pencils in engagementwith the record strip during operation ofthedevice,

a convenient means comprising Ascrew -i and 1$),'that are provided, respectively, upon eating motion is impa pawls 21 engage the ratchet 17 and c that thread rotatably mounted posts and the outer ends of which p-ovidcd with heads i6 and forked posts which the headed ends of the screws are adapted to engage. I

In'the operation or i she device, a reciprorted to the frame proportional to the motion of the engine pisiton and :this' motion is converted into a hhrmonic unidirectional motion which is applied tot-he feed roll 13 as will he expiained presently. if the a ame 25 is first moved to the left (Figs. 2 and 3) the rack 2-7 will cause thepinion 18 to rotate in such a direction ed roll 13, be i. Wise direction. As the indi are connected W' engine cylinder, to. penci vertically in opposite dire/ebonand trace the variations in pressure upon the record figure, it may be su posed that traced by the penci 5 and line 50 is traced by the pe strip. The form of the record th t is produced is well illustrated in Fig. i.

a Considering this the line 4 8 is the line 49 by the pencil 6, the one being for the head end oi the cylinder and the otherfor the crank end. The

o l 40 and indicates the lineoi atmospheric pressure. In order to determine the mean. e'li'ective pressure for any stroke, such that between the ordinates 51 and-'52, the area of tire diagram traced by the penci between the ordinates mustbe measured or calculated. it Will be observed that the lines and &9 cross each other at and that there are two areas inclosed by the lines, the larger to the rightof the point 53 and the smaller to the lo I The explanation is that the fluid-pres- .sure moves the piston from the right to the point- 53, and the inertia of the iiy wheel and other moving parts of the engine moves the .plston from the point 53 to the end of the stroke.- it will, of course, be understood that thearca between the. lines to the left of 53 should be subtracted from that to the right in determining the mean efi'ective pressure. The area to the left of 53 Will vary according to the characteristicsof an engine; that is, for high speed engines with high: compression this area will be greater than is here shown. Means may also be provided for recording in.- tervals of time-upon the strip, a convenient record comprising a dot 'or' other mark 54 made by means of a pencil 55 carried by an arm 56 that is actuated by an electromagnet 57 the circuit of which may he go vsrned by a clock (not shown) and completed periodically,

for instance, every second. 111 this manner the speed. of the engine under any given conditions of operation may be determined,

Since the present device records continuously the pressure variations in both ends of an engine cylinder, and since the simultaneous pressure values appear upon substanfamily the same ordinates, its use permits of obtaining much new information, as Well as of some more accurate information than has heretofore been obtainable, with the result that it has been found particularly adapted to the investigation of the operation of reversing engines, and such as are subjected to wide fluctuations of load, as,'for example, rolling mill engines. The device renders it possible. to determine the amount of steam consumed in reversing an engine, and to compare the cost of operation of a reversing en- The structural details of the device may obviously be varied Wiiullll considerable limits without n'iodiiying the mode of operation thereof or departing materially from the spirit of the invention.

I claim as my invention:

1. The combination with anengine cylinder, of means for efiecting unsuperposed continuous records of the pressure variations in both ends of the cylinder, the simultaneous pressure values being recorded upon substantially the same ordinates.

2. In an engine indicator, the combina tion with means for moving a record strip continuously and harmonically in one direction only at a rate proportional to the rate oi? movement of the engine piston, of means for simultaneously and continuously effecting records of the pressure variations in both ends oi an engine cylinder, the simultaneous pressure values being recorded upon substantially the same ordinates.

3. ln continuous indicator, the combination with two pressure recording de vices, of a reciprocating part, racks carried thereby, a feed roll, a spindle therefor, ratchets rigidly secured to the spindle, pinions loosely mounted upon the-spindle that mesh respectively with the racks carried by the reciprocating part, and sets of pawls that are carried by the pinions and that engage the adjacent ratchets. v

4. in a continuous indicator, the combirmtion with two pressure recording de vices, of a reolprooetmg pert, racks curried thereby, n'leeus for .nornmiiy maintaining the adjacent; ratchets.

5. loan engine indicator, the combine.- tion with means for movin e record strip continuously and herl nonicejly in one direc tion only at a rate proportional to the rate of movement of the engine piston, of me simultaneously and continuously or eirw records of too pressure variations in botn ends of an engine cylinder, the simuiteueous stzuitially the some ordinates and the records for successive strokes of the engine being "err-- superposed.

In testimony whereof, 1 have hereimfio subscribed my name this 26th day 0% Joe uavry, 190G.

MILTON W. IHBGLEE. Witnesses ()Tro S. SOHAIREIL BmNEY HINEs.

pressure values being recorded upon sub- 20 

